Technical Field
[0001] The present invention relates to an air conditioner blowing temperature estimation
apparatus and program, and particularly relates to estimation of a blowing temperature
from an air conditioner that uses a refrigerant.
Background Art
[0002] In heating operation of air conditioners that use refrigerant, defrosting of an outdoor
unit must be performed during operation and, at that time, cold air is blown from
an indoor unit. To solve this, measures have been implemented in which a blowing temperature
is monitored and, when the blowing of cold air is detected, a total air volume is
reduced. In the background art, technology has been proposed to estimate a blowing
temperature from a pipe temperature of a heat exchanger without using a temperature
sensor to measure the blowing temperature (e.g. Patent Literature 1).
Citation List
Patent Literature
Summary of Invention
Technical Problem
[0004] The outdoor unit of an air conditioner supplies the refrigerant to the indoor unit
through refrigerant piping that extends from the outdoor unit to the indoor unit and,
for example, in the case of cooling operation, it is known that when the blowing temperature
is warmer than a temperature of the refrigerant piping (gas pipe, liquid pipe), the
blowing temperature is strongly influenced by the refrigerant piping temperature.
Additionally, when the refrigerant piping is not completely sufficiently cooled, the
blowing temperature is influenced by an intake temperature.
[0005] However, in the background art, the blowing temperature from the indoor unit has
not been estimated by considering a difference in a state of the temperature of the
refrigerant piping in such air conditioners.
[0006] An object of the present invention is to estimate the blowing temperature from the
indoor unit by considering the state of the air conditioner.
Solution to Problem
[0007] An air conditioner blowing temperature estimation apparatus according to the present
invention includes:
refrigerant piping temperature acquisition means to acquire a measured temperature
of refrigerant piping connected to a heat exchanger of an indoor unit;
intake temperature acquisition means to acquire a measured temperature of an intake
port of the indoor unit;
determination means to determine an operating state of the indoor unit on the basis
of the measured temperature acquired by the refrigerant piping temperature acquisition
means and the measured temperature acquired by the intake temperature acquisition
means; and
estimation means to estimate a blowing temperature from the indoor unit on the basis
of the measured temperature acquired by the refrigerant piping temperature acquisition
means, the measured temperature acquired by the intake temperature acquisition means
and, among estimation models of the blowing temperature of the indoor unit, an estimation
model set in accordance with the operating state determined by the determination means.
[0008] The estimation means adjusts an estimated value of the blowing temperature so that
the estimated value continuously changes when switching the estimation model as a
result of transitioning from a present operating state of the indoor unit to a different
operating state. In the adjustment, the estimation means adjusts an output of the
estimated value considering the degree of influence of the plurality of estimation
models.
[0009] The air conditioner blowing temperature estimation apparatus includes:
detection means to detect an abnormality of the blowing temperature from the indoor
unit by analyzing a chronological change in an estimation temperature by the estimation
means; and
notification means to notify that an abnormality has been detected by the detection
means.
[0010] The air conditioner blowing temperature estimation apparatus further includes command
means to command operation control means of the indoor unit so that, when an estimation
temperature by the estimation means deviates from a target value of the blowing temperature,
the estimation temperature by the estimation means approaches the target value.
[0011] A program according to the present invention is for causing a computer to function
as:
refrigerant piping temperature acquisition means to acquire a measured temperature
of refrigerant piping connected to a heat exchanger of an indoor unit;
intake temperature acquisition means to acquire a measured temperature of an intake
port of the indoor unit;
determination means to determine an operating state of the indoor unit on the basis
of the measured temperature acquired by the refrigerant piping temperature acquisition
means and the measured temperature acquired by the intake temperature acquisition
means; and
estimation means to estimate a blowing temperature from the indoor unit on the basis
of the measured temperature acquired by the refrigerant piping temperature acquisition
means, the measured temperature acquired by the intake temperature acquisition means
and, among estimation models of the blowing temperature of the indoor unit, an estimation
model set in accordance with the operating state determined by the determination means.
Advantageous Effects of the Invention
[0012] According to the present invention, the blowing temperature from the indoor unit
is estimated by considering the state of the air conditioner. As such, accuracy of
the estimated value of the blowing temperature can be improved.
[0013] Additionally, even when switching the estimation model in accordance with a change
in the state of the air conditioner, it is possible to prevent the estimated value
of the blowing temperature from changing in an extreme manner.
[0014] Furthermore, abnormalities of the blowing temperature can be detected by analyzing
the estimated blowing temperature.
[0015] Moreover, when the estimated blowing temperature deviates more than a predetermined
amount from the target value, the operation of the air conditioner can be controlled
so as to approach the target value.
Brief Description of the Drawings
[0016]
Fig. 1 is a block configuration diagram illustrating an embodiment of an air conditioner
blowing temperature estimation apparatus according to the present invention;
Fig. 2 is a hardware block configuration diagram of the air conditioner blowing temperature
estimation apparatus of a first embodiment;
Fig. 3 is a flowchart illustrating estimation processing of a blowing temperature
from an indoor unit of the first embodiment;
Fig. 4 is a drawing illustrating, as a graph, estimation models set for each operating
state of the first embodiment;
Fig. 5 is a block configuration diagram of an air conditioner blowing temperature
estimation apparatus of a second embodiment; and
Fig. 6 is a block configuration diagram of an air conditioner blowing temperature
estimation apparatus of a third embodiment.
Description of Embodiments
[0017] Next, preferred embodiments of the present invention will be described while referencing
the drawings.
First Embodiment
[0018] Fig. 1 is a block configuration diagram illustrating an embodiment of an air conditioner
blowing temperature estimation apparatus according to the present invention. Fig.
1 illustrates an outdoor unit 1, an indoor unit 2, a heat exchanger 3 installed in
the indoor unit 2, a liquid pipe 4 and a gas pipe 5 as refrigerant piping and extending
from the outdoor unit 1 to the heat exchanger 3, sensors 6, 7, and 8 to measure temperatures
of the liquid pipe 4, the gas pipe 5, and an intake port (not illustrated in the drawing)
of the indoor unit 2, and a signal line 9 for an air conditioner controller 20 to
receive sensor data from the outdoor unit 1 and the indoor unit 2 of the air conditioner.
Existing equipment may be used without modification for these components. The present
embodiment is implemented by adding an air conditioner blowing temperature estimation
apparatus 10 to the configuration described above,
[0019] Fig. 2 is a hardware configuration diagram of a computer forming the air conditioner
blowing temperature estimation apparatus 10 of the present embodiment. In the present
embodiment, the computer forming the air conditioner blowing temperature estimation
apparatus 10 can be realized using a general-purpose hardware configuration such as
a conventionally existing personal computer (PC). That is, as illustrated in Fig.
2, the computer is configured by connecting, to an internal bus 40, a CPU 31, a ROM
32, a RAM 33, a HDD 34, an input/output controller 38 to connect each of a mouse 35
and a keyboard 36 provided as input means and a display 37 provided as a display device,
and a network controller 39 provided as communication means. "CPU" is an abbreviation
for "Central Processing Unit". "ROM" is an abbreviation for "Read Only Memory". "RAM"
is an abbreviation for "Random Access Memory" and "HDD" is an abbreviation for "Hard
Disk Drive".
[0020] The CPU 31, the ROM 32, the RAM 33, and the HDD 34 are referred to collectively as
"processing circuitry".
[0021] Returning to Fig. 1, the air conditioner blowing temperature estimation apparatus
10 of the present embodiment includes a data acquisition unit 11, an operating state
determination unit 12, a blowing temperature estimation unit 13, a blowing temperature
display unit 14, and a blowing temperature estimation model storage unit 21. The air
conditioner controller 20 periodically collects, from the air conditioner, various
measured temperatures taken by the sensors 6, 7, and 8 of the liquid pipe 4, the gas
pipe 5, and the intake port. The data acquisition unit 11 is provided as refrigerant
piping temperature acquisition means and intake temperature acquisition means and
periodically, every one minute, for example, acquires these various measured temperatures
from the air conditioner controller 20 as latest measured temperatures. The operating
state determination unit 12 is provided as determination means and determines an operating
state of the indoor unit 2 on the basis of the various measured temperatures acquired
by the data acquisition unit 11. The blowing temperature estimation unit 13 is provided
as estimation means and estimates the blowing temperature from the indoor unit 2 on
the basis of the various measured temperatures acquired by the data acquisition unit
11 and an estimation model of the blowing temperature from the indoor unit 2, wherein
the estimation model is set in accordance with the operating state determined by the
operating state determination unit 12. The blowing temperature display unit 14 displays
an estimated value, obtained by estimation, of the blowing temperature from the indoor
unit 2 on the display 37. The estimation model set in accordance with the operating
state of the indoor unit 2 is stored in the blowing temperature estimation model storage
unit 21.
[0022] The various constituents 11 to 14 of the air conditioner blowing temperature estimation
apparatus 10 are realized by coordinated operations between the computer forming the
air conditioner blowing temperature estimation apparatus 10 and programs executed
by the CPU 31 installed in the computer. Additionally, the blowing temperature estimation
model storage unit 21 is realized by the HDD 34 installed in the air conditioner blowing
temperature estimation apparatus 10. Alternatively, the RAM 33 may be used as the
blowing temperature estimation model storage unit 21, or external storage means may
be used across a network as the blowing temperature estimation model storage unit
21.
[0023] The programs used in the present embodiment may obviously be provided by communication
means or may be provided by being stored on a computer-readable recording medium such
as a CD-ROM or USB memory. CD-ROMs, USB memory, and similar recordable media are non-temporary,
tangible media. "CD-ROM" is an abbreviation for "Compact Disc-ROM" and "USB" is an
abbreviation for "Universal Serial Bus". The programs provided from the communication
means or the recording medium are installed on the computer, and the CPU 31 of the
computer sequentially executes the programs to realize various types of processing.
[0024] The air conditioner and the refrigerant have a plurality of states. Specifically,
an operating state in which a switch is switched from OFF to ON to perform heating
operation (hereinafter referred to as "heating thermo ON"), a state in which the switch
is conversely switched from ON to OFF (hereinafter referred to as "heating thermo
OFF"), an operating state in which a switch is switched from OFF to ON to perform
cooling operation (hereinafter referred to as "cooling thermo ON"), and a state in
which the switch is conversely switched from ON to OFF (hereinafter referred to as
"cooling thermo OFF"). The transition of the blowing temperature from the indoor unit
2 is thought to vary depending on the state of the air conditioner. Even when in the
heating thermo ON state, the blowing temperature from the indoor unit 2 varies between
when in a state in which the refrigerant piping (the liquid pipe 4 and the gas pipe
5) is not sufficiently warmed (hereinafter referred to as "transient state") and when
in a state in which the transient state has passed (hereinafter referred to as "steady
state"). The blowing temperature varies between the transient state and the steady
state when in the cooling thermo ON state as well. The present embodiment is characterized
by estimating the blowing temperature from the indoor unit 2 by considering the state
of the air conditioner. The blowing temperature from the indoor unit 2 is a temperature
of a blowing port of the indoor unit 2, that is, a temperature of air blown from the
blowing port of the indoor unit 2.
[0025] When in heating operation, the air volume introduced from the intake port is reduced
in the transient state of the heating thermo ON and the heating thermo OFF. As such,
the blowing temperature is less likely to be influenced by the temperature near the
intake port or the room temperature. Therefore, in the present embodiment, an estimation
model is set in which the refrigerant piping temperature is used as the blowing temperature
without considering the intake port temperature. Note that, in the present embodiment,
the temperatures of two types of refrigerant piping, namely the liquid pipe 4 and
the gas pipe 5, are measured. As such, the average value of the measured temperatures
is used as the refrigerant piping temperature. When in the steady state of the heating
thermo ON, an estimation model is set in which the average value of the refrigerant
piping temperature and the intake port temperature is used as the blowing temperature.
Thus, in the present embodiment, the estimation model is set in accordance with the
operating state.
[0026] When in cooling operation, the blowing temperature is more likely to be influenced
by the intake port temperature in the transient state of the cooling thermo ON and
the cooling thermo OFF. This is thought to be due to the fact that warm air rises
and is more likely to accumulate near the intake port. Accordingly, the estimation
model is set in which the average value of the refrigerant piping temperature and
the intake port temperature is used as the blowing temperature. When in the steady
state of the cooling thermo ON, an estimation model is set in which an offset value
(e.g. 3°C) is added to the refrigerant piping temperature.
[0027] Next, estimation processing of the blowing temperature from the indoor unit 2 of
the present embodiment will be described while referencing the flowchart illustrated
in Fig. 3. As an example, a case is described for heating operation.
[0028] As described above, the data acquisition unit 11 acquires the various measured temperatures
of the liquid pipe 4, the gas pipe 5, and the intake port sent periodically from the
air conditioner controller 20 (step 110). An acquisition interval is not particularly
limited, but when set to acquire in a long cycle such as five minutes, errors are
more likely to occur, particularly in the transient state. As such, the acquisition
interval was set to one minute in the present embodiment. When the data acquisition
unit 11 acquires the various measured temperatures, the operating state determination
unit 12 determines the operating state of the indoor unit 2 on the basis of those
measured temperatures (step 120). In the present embodiment, the operating state is
determined by a value obtained by subtracting the intake port temperature from the
refrigerant piping temperature. Moreover, the operating state is determined from a
magnitude relationship between a numerical value representing the operating state
and a threshold value. That is, in the present embodiment, the operating state is
determined from the magnitude relationship between the value obtained by subtracting
the intake port temperature from the refrigerant piping temperature (the numerical
value representing the operating state) and the threshold value.
[0029] Next, the blowing temperature estimation unit 13 identifies the estimation model
set in accordance with the determined operating state (step 130), and substitutes
the various measured temperatures into that estimation model to calculate the estimated
value of the blowing temperature from the indoor unit 2 (step 140). When the estimated
value of the blowing temperature is thusly calculated, the blowing temperature display
unit 14 displays that estimated value on the display 37 (step 150). Note that, in
the present embodiment, the estimated value is displayed, but the estimated value
may also be sent to a computer across a network or the estimated value may be stored
in predetermined storage means.
[0030] Fig. 4 is a drawing illustrating, as a graph, the estimation model set for each of
the operating states. According to the example illustrated in Fig. 4, when a numerical
value S representing the operating state is less than a threshold value s1, estimation
model M1 is selected and, when the numerical value S representing the operating state
is greater than or equal to a threshold value s2, estimation model M2 is selected.
Note that, when in the heating operation, the estimation model M1 corresponds to the
estimation model corresponding to the transient state of the heating thermo ON, and
the estimation model M2 corresponds to the estimation model corresponding to the steady
state of the heating thermo ON. Although s1 and s2 may be identical values, in this
case, s1 < s2, as illustrated in Fig. 4. As illustrated in Fig. 4, when the estimation
models M1 and M2 do not intersect between s1 and s2, there is a possibility that the
estimated value will greatly change when switching between estimation models. As such,
in the present embodiment, estimated values between s1 and s2 are adjusted so as to
change continuously and smoothly without becoming discontinuous. In order to achieve
this, the estimated value is calculated by weighting the estimation models M1 and
M2.
[0031] In one example, a weighting t is calculated using the equation t = (s2 - S) / 2.
Then, the estimated value between s1 and s2 is calculated using the following equation:
Estimated value = estimated value based on estimation model M1 × t + estimated value
based on estimation model M2 × (1-t)
In this case, the estimated value changes continuously and smoothly as illustrated
by a line 41 in Fig. 4.
[0032] According to the present embodiment, as described above, the estimation model is
set in accordance with the operating state of the indoor unit 2, and the estimation
model, corresponding to the state of the air conditioner determined on the basis of
the various measured temperatures of the liquid pipe 4, the gas pipe 5, and the intake
port, is selected. The blowing temperature from the indoor unit 2 is estimated using
the selected estimation model and, as such, the accuracy of the estimated value of
the blowing temperature can be improved.
[0033] Note that, in the present embodiment, the average value of the various measured temperatures
of the liquid pipe 4 and the gas pipe 5 is used as the refrigerant piping temperature
to accurately estimate the blowing temperature, but configurations are possible in
which only one of the measured temperatures is used.
Second Embodiment
[0034] Fig. 5 is a block configuration diagram of an air conditioner blowing temperature
estimation apparatus of the present embodiment. Note that constituents identical to
constituents described in the first embodiment are marked with the same reference
signs and descriptions thereof are appropriately forgone. In addition, the hardware
configuration may be identical to that of the first embodiment.
[0035] The air conditioner blowing temperature estimation apparatus 10 in the present embodiment
includes an abnormality detection unit 15 and a blowing temperature trend log storage
unit 22 in addition to the components described in the first embodiment. The abnormality
detection unit 15 is realized by coordinated operations between the computer and programs
executed by the CPU 31 installed in the computer, and the blowing temperature trend
log storage unit 22 is realized by the HDD 34. In the first embodiment, the estimated
value of the blowing temperature is simply displayed but, in the present embodiment,
a blowing temperature trend log, which is chronological data of the estimated values
of the blowing temperature, is accumulated so that the transition of the estimated
value of the blowing temperature will be understood.
[0036] Moreover, the abnormality detection unit 15 detects abnormalities in the blowing
temperature from the indoor unit 2 by chronologically analyzing the estimated values
of the blowing temperature accumulated in the blowing temperature trend log storage
unit 22. In one example, an abnormality is determined when an amount of change obtained
from an estimated value of the blowing temperature obtained on the basis of a measured
temperature acquired immediately before, and an estimated value of the blowing temperature
obtained on the basis of a measured temperature presently acquired exceeds a threshold
value.
[0037] When the abnormality detection unit 15 detects an abnormality in this manner, the
blowing temperature display unit 14, as notification means, notifies a maintenance
worker of the occurrence of the abnormality by displaying a message indicating that
an abnormality was detected, together with the estimated value of the blowing temperature.
Third Embodiment
[0038] Fig. 6 is a block configuration diagram of an air conditioner blowing temperature
estimation apparatus of the present embodiment. Note that constituents identical to
constituents described in the first embodiment are marked with the same reference
signs and descriptions thereof are appropriately forgone. Additionally, the hardware
configuration may be identical to that of the first embodiment.
[0039] The air conditioner blowing temperature estimation apparatus 10 in the present embodiment
includes a control command unit 16 and a blowing temperature setting information storage
unit 23 in addition to the components described in the first embodiment. The control
command unit 16 is realized by coordinated operations between the computer and programs
executed by the CPU 31 installed in the computer, and the blowing temperature setting
information storage unit 23 is realized by the HDD 34. In the first embodiment, the
processing ends with the simple displaying of the estimated value of the blowing temperature,
but in the present embodiment, processing is performed that extends to operation control
of the indoor unit 2.
[0040] A target value of the blowing temperature from the indoor unit 2 is preset as blowing
temperature information in the blowing temperature setting information storage unit
23. Note that, the target value set in the blowing temperature setting information
storage unit 23 may be a single target value or may be set for each operating state.
When the estimated value of the blowing temperature by the blowing temperature estimation
unit 13 deviates from the target value of the blowing temperature, the control command
unit 16, as command means, commands the air conditioner controller 20, as operation
control means of the indoor unit 2 so that the estimated value of the blowing temperature
by the blowing temperature estimation unit 13 approaches the target value. The air
conditioner controller 20 that has received the command controls the operations of
the indoor unit 2 so that the estimated value of the blowing temperature approaches
the target value.
[0041] Supplementary explanation is given below.
[0042] The estimation of the blowing temperature is performed periodically. In one example,
the estimation of the blowing temperature is performed on a 30-second cycle. Changes
in the operating state of the air conditioner are considered each cycle. Therefore,
even if a blowing temperature sensor is not provided, feedback control of the blowing
temperature using the estimated value is possible. As such, provided that the control
is performed correctly, the indoor unit 2 will operate so as to reduce the deviation
between the estimated value and the target value of the blowing temperature. Typical
feedback control is anticipated as the control by the air conditioner controller 20
on the operations of the indoor unit 2. As output, the refrigerant piping temperature
is controlled. A target value of the refrigerant piping temperature can be calculated
as follows. When a target temperature and a room temperature are given in the estimation
model, candidates for the target refrigerant piping temperature can be reverse-calculated.
Since there are a plurality of unknowns, a solution cannot be uniquely determined,
but a solution can be selected by applying a control condition of minimizing energy
efficiency on the basis of a state of a refrigeration circuit. The air conditioner
controller 20 controls an expansion valve of the indoor unit, a compressor of the
outdoor unit, or the like so that the refrigerant piping temperature approaches the
selected temperature.
[0043] Cases in which the estimated value deviates from the target value are cases where
the difference between the estimated value and the target value is greater than or
equal to a predetermined threshold value.
[0044] According to the present embodiment, it is possible to support the operation control
of the indoor unit 2 as described above.
[0045] Note that the configurations described above in the first to third embodiments may
be appropriately combined and used. Additionally, in the present embodiments, an example
is described in which the air conditioner blowing temperature estimation apparatus
10 is a PC, but is not limited thereto and, for example, a configuration is possible
in which the processing functions of the air conditioner blowing temperature estimation
apparatus 10 are incorporated into the air conditioner controller 20.
Reference Signs List
[0046] 1: outdoor unit, 2: indoor unit, 3: heat exchanger, 4: liquid pipe, 5: gas pipe,
6, 7,8: sensor, 9: signal line, 10: air conditioner blowing temperature estimation
apparatus, 11: data acquisition unit, 12: operating state determination unit, 13:
blowing temperature estimation unit, 14: blowing temperature display unit, 15: abnormality
detection unit, 16: control command unit, 20: air conditioner controller, 21: blowing
temperature estimation model storage unit, 22: blowing temperature trend log storage
unit, 23: blowing temperature setting information storage unit, 31: CPU, 32: ROM,
33: RAM, 34: HDD, 35: mouse, 36: keyboard, 37: display, 38: input/output controller,
39: network controller, 40: internal bus.